Glacier Fed: Investigating marine iron within Berners Bay

Abstract

Marine iron is generally considered a limiting nutrient, especially within the Gulf of Alaska. While it is known that glaciers in Southeast Alaska contribute essential nutrients to the marine environment, there is little information regarding fluxes and bioavailability of iron transported from glacial rivers to coastal waters in the region. Berners Bay, north of Juneau, is a tidal estuary that is substantially influenced by three converging glacial rivers. The goal of this research is to gain an understanding of total dissolved iron within Berners Bay and ascertain a potential gradient in iron concentrations from the estuary into Lynn Canal while evaluating other oceanographic parameters such as chlorophyll-α. Water samples will be collected during the summer of 2015 at eight stations along two separate transects throughout Berners Bay. Iron concentrations will be determined at the University of Alaska Southeast using Chelex-100 resin and graphite furnace atomic absorption spectrometry. This study has the potential to determine baseline marine nutrient values and support future nutrient work within these dynamic glacial systems.